After the G-7 summit, Trudeau hosted a news conference where he said that the Canadian government "did not take" the US tariffs against Canada lightly.

Expressing a commitment to modernize the World Trade Organization "to make it more fair as soon as possible", the communique said, "We strive to reduce tariff barriers, non-tariff barriers and subsidies". At the same time, the media suggests that by the next day "the consensus had unraveled".

But with the summit ending in a war of words, Abe's attempt to defuse the conflict over USA trade policy during the meeting apparently had little effect on Trump after all. Nor did the United States administration want to sign a charter regarding plastic in the ocean.

"PM Justin Trudeau of Canada acted so meek and mild during our @G7 meetings only to give a news conference after I left saying that. he 'will not be pushed around.' Very dishonest & weak", he added.

President Donald Trump shakes hands with Canada's Prime Minister Justin Trudeau in a bilateral meeting at the G-7 summit in in Charlevoix, Quebec, Canada, June 8, 2018.

"That's what bad-faith Justin Trudeau did with that stunt press conference", Navarro said.

In view of threatened USA tariffs on auto imports, which would particularly affect Germany, Grenell said that he was a "big vehicle fan" and knew how important the industry was.

He added that Trump "is not going to let a Canadian prime minister push him around ... on the eve of this - he is not going to permit any show of weakness on a trip to negotiate with North Korea".

"Our Tariffs are in response to his of 270% on dairy!" the USA president tweeted.

Nearly as an afterthought, Trump - now in Singapore for a summit with North Korean leader Kum Jong Un - tweeted: "Great to be in Singapore, excitement in the air!"

While G7 members have been sharing concerns over North Korea, disputes with the United States over trade have been escalating.

Twitter conspiracy theorists have gone into a meltdown over them, with many replacing cries of "Fake News" with 'Fake Brows'.

Mr Kudlow accused the Canadian PM of betraying Mr Trump with "polarising" statements on trade policy that risked making the USA leader look weak ahead of a historic summit with North Korean leader Kim Jong-un.

Larry Kudlow, director of the U.S. National Economic Council, said on CNN that Trudeau engaged in "betrayal" and "stabbed us in the back". I don't blame them.

Tusk's comments came shortly after President Trump's trade adviser Peter Navarro said there was a "special place in hell" for leaders who betrayed Trump. How many women wear false eyebrows? "We must put the American worker first!" he tweeted later. Minimum is 17B. Tax Dairy from us at 270%.

Although Trump and Kudlow have since claimed Trudeau "stabbed us in the back" and was the reason for the U-turn, it is Trump's actions that other G7 leaders appeared to find frustrating.